my 87 TII when i start it will die if i dont give it gas constantly, and will die within like 5 mins, finally after five mins it wont and it idles around 1000 and my engine jumps and chugs almost all the time and the idle does bounce up and down, i dunno wats wrong and have askd around with no answer, so this is number 1..


secondly when revd to about 6 or 7 the exhaust back fires... dunno about that either.....

please help i wanna get this to it full potential but cant when i keep running in to all these problems... thank you

 

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Sounds to me like you have a pretty large vacuum leak. Check all the usual suspects. Spray some carb cleaner around the joints between the TB and the UIM and the UIM and LIM while the engine is idling. If you notice a smoothing out and improvement in the idle, you have a worn out or torn gasket.

Other than that I would suspect fuel pump pressure, clogged fuel filter or maybe even a clogged Cat.

 

yeah, sounds like a lac leak to me too. What gives it away is the backfire at high rpms and the chugging at idle. My mx6 turbo is notorious for producing leaks along the intercooler piping. Just because of the age of the rubber, when things like the tb get too hot they crack the piping and just normal weathering. That might not be the case with yours but the symptoms are the same.

 

how do you locate a vacuum leak?

 

^ is there a way or do you just look for holes?

 

There's not really a good way to do it. You can pump compressed air into the system and listen for leaks. You could look for them. You can listen for them with the engine on (good luck if it's a small leak).